import { JSONAPISerializer } from '@warp-drive/legacy/serializer/json-api';

export default class ApplicationSerializer extends JSONAPISerializer {
  /**
      Parse the links in the JSONAPI response and convert to a meta-object.
      Inlined from the ember-data-table package.
  */
  normalizeQueryResponse(store, clazz, payload) {
    const result = super.normalizeQueryResponse(...arguments);
    result.meta = result.meta || {};

    if (payload.links) {
      result.meta.pagination = createPageMeta(payload.links);
    }
    if (payload.meta) {
      result.meta.count = payload.meta.count;
    }

    return result;
  }
}

/**
   Transforms link URLs to objects containing metadata
   E.g.
   {
       previous: '/streets?page[number]=1&page[size]=10&sort=name
       next: '/streets?page[number]=3&page[size]=10&sort=name
   }

   will be converted to

   {
       previous: { number: 1, size: 10 },
       next: { number: 3, size: 10 }
   }
 */
function createPageMeta(data) {
  let meta = {};

  Object.keys(data).forEach((type) => {
    const link = data[type];
    meta[type] = {};

    if (link) {
      //extracts from '/path?foo=bar&baz=foo' the string: foo=bar&baz=foo
      const query = link.split(/\?(.+)/)[1] || '';

      query.split('&').forEach((pairs) => {
        const [param, value] = pairs.split('=');

        if (decodeURIComponent(param) === 'page[number]') {
          meta[type].number = parseInt(value);
        } else if (decodeURIComponent(param) === 'page[size]') {
          meta[type].size = parseInt(value);
        }
      });
    }
  });

  return meta;
}